A rare alignment of two exoplanets with their star, marking one of the few known exosyzygies, an astronomical event involving ...

Planets usually stay close to their host stars, tracing steady paths shaped by gravity. Yet some planets break free and drift ...

For the first time, astronomers have directly measured the mass of a rogue planet, a celestial body wandering through space ...

In doing so, they found this orphan is within the same weight class as Saturn, strengthening the case that the galaxy teems ...

While most planets that we are familiar with stick relatively close to their host star in a predictable orbit, some planets ...

Their analysis showed that the planet lies about 3,000 parsecs, or just under 10,000 light-years, from Earth. Its mass is ...

A lucky alignment of space- and ground-based telescopes has enabled researchers to nail down the mass of a rogue planet for the first time. Unlike worlds in our Solar System, rogue planets do not ...

Somewhere between the stars, far from any sun, a planet is moving quietly through space. There is no orbit to trace and no ...

A visible line of planets has for weeks been the talk of astronomers and hobbyist stargazers who have sought to catch a sight of our solar system's worlds. Online chatter and a frenzy of media ...

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers ...